Temperature non-uniformity is a major design challenge in the design of Rapid Thermal Processing chambers. Temperature uniformity between 5° C. and 10° C. across a substrate is helpful in achieving a high quality of deposition or annealing all around the substrate. In this regard, temperature uniformity is defined as the difference between a maximum temperature measured at any point on a substrate and a minimum temperature measured concurrently at any point on the substrate. The substrate may be heated using conductive heaters or radiation. Several methods are conventionally used to control temperature uniformity of a substrate during processing, including use of reflective and/or absorptive shields, liners, specially designed coil layout inside the heater, and power supply control. Despite these measures, temperature uniformity still remains a major issue. Non-uniformity may result because of the differential heating of a substrate from the heater below.
Therefore, there exists a need for a susceptor that provides improved temperature uniformity of a substrate during thermal processing.